Slot Machine

ABSTRACT

A slot machine according to the present invention includes a symbol matrix display area, second reels having second symbols arranged in a superimposed manner on first symbols of first reels, and a processor for controlling rotation of the first and second reels. The plurality of first reels each has an independent rotation axis. Rotation axis of each second reel is positioned closer to a rear side compared to that of each first reel when viewed from the symbol matrix display area. The processor awards a prize in the case where a combination of the first symbols of the first reels rearranged in the symbol matrix display area and the second symbols of the second reels rearranged in a superimposed manner on the first symbols of the first reels is a winning combination on an activated line in a column, row, or diagonal direction.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority of U.S. Provisional Application No. 61/033,932 filed on Mar. 5, 2008. The contents of this application are incorporated herein by reference in their entirety.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a slot machine.

2. Description of the Related Art

In a conventional slot machine, when a player inserts a game medium, such as a coin and a bill, in an insertion slot of a slot machine and presses a SPIN button, a display provided on a front face of a cabinet displays a plurality of symbols in a scrolling manner. Then, scrolling of each of the symbols automatically stops.

As such a slot machine, for example, as disclosed in U.S. Pat. No. 6,093,102, a slot machine exists which employs a concept of a winning line. In this concept, in case a combination of symbols rearranged on a winning line is a predetermined winning combination, a predetermined number of game media are paid out.

In addition, as such a slot machine, for example, as disclosed in each of U.S. Pat. No. 6,604,999 and U.S. Patent Publication No. 2002/0065124, a slot machine exists which provides two types of payouts, including a payout determined by a combination of symbols rearranged on a winning line and a payout determined by a number of displayed scatter symbols.

In the above-described conventional slot machine, a position of a winning line on which a winning combination is established or a displaying position of a scatter symbol is not related to a payout. Accordingly, a prolonged need exists for the advent of a slot machine which is capable of offering new entertainability.

The present invention has been made in view of the above-described circumstance. It is an object of the present invention to provide a novel slot machine by enhancing entertainability associated with rearrangement of the symbols.

SUMMARY OF THE INVENTION

A first aspect of the present invention is a slot machine including: a symbol matrix display area in which a plurality of symbols are arranged in column and row directions; a plurality of first reels provided corresponding to individual fields of the symbol matrix display area, the first reels having plural types of first symbols arranged thereon respectively; a plurality of second reels each having a larger diameter than that of each of the first reels, the plurality of second reels being disposed at outer peripheral sides of the plurality of first reels so as to enclose part of the plurality of first reels provided in a column direction, the plurality of second reels each having a plurality of second symbols arranged thereon, the second symbols being arranged in a superimposed manner on the first symbols on the first reels disposed in the symbol matrix display area; a plurality of first motors for driving the plurality of first reels, respectively, in a rotational manner; a second motor for driving the second reels in a rotational manner; and a processor for controlling rotation of the first and second reels by controlling the first and second motors. The plurality of first reels each have an independent rotation axis respectively. The second reels each have a rotation axis positioned closer to a rear side in comparison with that of each of the first reels when viewed from the symbol matrix display area. The processor is programmed to: (a) control rotation of the plurality of first reels to rearrange, in the symbol matrix display area, the first symbols arranged on the first reels; (b) control rotation of the second reels to rearrange, in the symbol matrix display area, the second symbols arranged on the second reels so as to superimpose the second symbols arranged on the second reels on the first symbols arranged on the first reels rearranged in the symbol matrix display area; and (c) award a prize in the case where a combination of the first symbols on the first reels rearranged in the symbol matrix display area and the second symbols on the second reels rearranged in a superimposed manner on the first symbols on the first reels is a winning combination on an activated line in a column, row, or diagonal direction.

According to the first aspect of the present invention, after the rearrangement of symbols, the symbols are further rearranged in a superimposed manner on the rearranged symbols. For example, in the case where the symbol “1Bar” is rearranged and then the symbol “3Bar” is rearranged thereon in a superimposed manner, a prize is to be awarded based on a payout corresponding to the symbol “3Bar”. Thus, the slot machine according to the first aspect raises players' expectations for a payout, thereby enhancing entertainability in rearrangement of symbols.

A second aspect of the present invention is a slot machine constituted as set fourth below. In the first aspect, each of the second symbols arranged on the second reel is set to a WILD symbol. The processor, in the itemized (c), awards a prize according to a combination of the first symbols on the first reels disposed in the symbol matrix display area and the plurality of WILD symbols contiguously rearranged on any one of the second reels.

According to the second aspect, after rearrangement of symbols, symbols are further rearranged in a superimposed manner on the rearranged symbols. For example, after rearrangement of the symbols, the plurality of symbols “WILD” can be rearranged thereon in a superimposed manner. Thus, the slot machine according to the second aspect raises players' expectations for a payout corresponding to the symbol “WILD”, thereby enhancing entertainability in rearrangement of symbols.

A third aspect of the present invention is a slot machine constituted as set fourth below. In the first aspect, the second reels each are made up of a predetermined symbol and a blank symbol.

According to the third aspect, after rearrangement of symbols, the symbols “WILD” are further rearranged in a superimposed manner on the rearranged symbols. For example, after rearrangement of symbols, the plurality of symbols “WILD” can be rearranged thereon in a superimposed manner. In this manner, the symbols “WILD” can be rearranged contiguously. Thus, the slot machine according to the third aspect raises players' expectations for a payout corresponding to the symbol “WILD”, thereby enhancing entertainability in rearrangement of symbols.

A fourth aspect of the present invention is a slot machine constituted as set fourth below. In the first aspect, the processor is further programmed to: (d) execute a basic game; (e) execute a free game in the case where a predetermined condition is met during the basic game; and (f) execute processes in the itemized (a) to (c) during the free game.

According to the fourth aspect, after rearrangement of symbols during the free game, the symbols “WILD” are further rearranged in a superimposed manner on the rearranged symbols. For example, after rearrangement of the symbols during the free game, the plurality of symbols “WILD” can be rearranged thereon in a superimposed manner. In this manner, players can visually recognize the symbols “WILD” that are contiguously rearranged. Thus, the slot machine according to the fourth aspect raises players' expectations for the free game, thereby enhancing entertainability in rearrangement of symbols.

A fifth aspect of the present invention is a slot machine including; a symbol matrix display area in which a plurality of symbols are arranged in column and row directions; a plurality of first reels provided corresponding to individual fields of the symbol matrix display area, the first reels having plural types of first symbols arranged thereon respectively; a plurality of second reels each having a larger diameter than that of each of the first reels, the plurality of second reels being disposed at outer peripheral sides of the plurality of first reels so as to enclose part of the plurality of first reels provided in a column direction, the plurality of second reels each having a plurality of second symbols arranged thereon, the second symbols being arranged in a superimposed manner on the first symbols on the first reels disposed in the symbol matrix display area; a plurality of first motors for driving the plurality of first reels, respectively, in a rotational manner; a second motor for driving the second reels in a rotational manner; and a processor for controlling rotation of the first and second reels by controlling the first and second motors. The plurality of first reels each have an independent rotation axis respectively. The second reels each have a rotation axis positioned closer to a rear side in comparison with that of each of the first reels when viewed from the symbol matrix display area. Each of the second symbols arranged on the second reels is set to a WILD symbol. The processor is programmed to: (a) control rotation of the plurality of first reels to rearrange the first symbols arranged on the first reels, in the symbol matrix display area,; (b) control rotation of the second reels to rearrange the second symbols arranged on the second reels, in the symbol matrix display area, so as to superimpose the second symbols arranged on the second reels on the first symbols arranged on the first reels rearranged in the symbol matrix display area; and (c) award a prize in the case where a combination of the first symbols on the first reels rearranged in the symbol matrix display area and the WILD symbols on the second reels rearranged in a superimposed manner on the first symbols arranged on the first reels is a winning combination on an activated line in a column, row, or diagonal direction.

According to the fifth aspect, after rearrangement of symbols, the symbols “WILD” are further rearranged on the rearranged symbols in a superimposed manner. For example, in the case where the symbol “1Bar” is rearranged and then the symbol “WILD” is rearranged thereon in a superimposed manner, a prize is to be awarded based on a payout corresponding to the symbol “WILD”. Thus, the slot machine according to the fifth aspect raises players' expectations that the symbols “WILD” would be rearranged on the activated line, thereby enhancing entertainability in rearrangement of symbols.

A sixth aspect of the present invention is a slot machine constituted as set fourth below. In the fifth aspect, the second reels each are made up of a predetermined symbol and a blank symbol.

According to the sixth aspect, after rearrangement of symbols, the symbols “WILD” are further rearranged on the rearranged symbols in a superimposed manner. For example, after rearrangement of symbols, the plurality of symbols “WILD” is further rearranged on the rearranged symbols other than the symbols “WILD”, in a superimposed manner. In this manner, players can visually recognize the symbols “WILD” that are contiguously rearranged. Thus, the slot machine according to the sixth aspect raises players' expectations for a payout corresponding to the symbol “WILD”, thereby enhancing entertainability in rearrangement of symbols.

A seventh aspect of the present invention is a slot machine constituted as set fourth below. In the fifth aspect, the processor is further programed to: (d) execute a basic game; (e) execute a free game in the case where a predetermined condition is met during the basic game; and (f) execute processes in the itemized (a) to (c) during the free game.

According to the seventh aspect, the symbols “WILD” are rearranged in a superimposed manner on the plurality of rearranged symbols during the free game. Thus, the slot machine according to the seventh aspect raises player's expectations that the symbols “WILD” would be rearranged on the activated line during the free game, thereby enhancing entertainability in rearrangement of symbols during the free game.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a view showing one example of symbol-rearrangement according to a first embodiment;

FIG. 2 is a perspective view schematically showing a slot machine according to the first embodiment;

FIG. 3 is a perspective view schematically showing a reel according to the first embodiment;

FIG. 4 is a view showing an internal construction of the slot machine shown in FIG. 2;

FIG. 5 is a view showing an internal construction of the reel shown in FIG. 4;

FIG. 6A is a view showing a correspondence relationship between various symbols and payouts at the time of a basic game according to the first embodiment;

FIG. 6B is a view showing a correspondence relationship between the various symbols and payouts at the time of the basic game according to the first embodiment;

FIG. 7A is a view showing one example of an image displayed in the slot machine shown in FIG. 2 according to the first embodiment;

FIG. 7B is a view showing one example of an image displayed in the slot machine shown in FIG. 2 according to the first embodiment;

FIG. 8 is a flowchart showing a subroutine of main process according to the first embodiment;

FIG. 9 is a flowchart showing a subroutine of a game execution process according to the first embodiment;

FIG. 10 is a flowchart showing a subroutine of symbol rearrangement process according to the first embodiment;

FIG. 11 is a flowchart showing a subroutine of a game execution process according to a second embodiment;

FIG. 12 is a flowchart showing a subroutine of a free game execution process according to the second embodiment;

FIG. 13 is a flowchart showing a subroutine of a symbol rearrangement process during the free game according to the second embodiment; and

FIG. 14 is a view showing one example of an image displayed during the free game in the slot machine shown in FIG. 2 according to the second embodiment.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

First, a slot machine 10 according to a first embodiment will be described in detail with reference to the drawings. Here, the slot machine according to the first embodiment described below is a so-called hybrid type slot machine, which has a transparent liquid crystal panel allocated in front of a plurality of mechanical reels supported in a rotatable manner, and executes a game by displaying images of various symbols drawn on an outer peripheral surface of the mechanical reels through the transparent liquid crystal panel.

FIG. 1 is a view showing one example of rearranged symbols according to the first embodiment. As shown in FIG. 1, a total of fifteen reels 101 a to 101 o in five rows and three columns are provided in a rotatable manner in a symbol display area 28. The reels 101 a to 101 o form a double-layered structure with level-up reels 102 a to 102 e that rotate outside the reels 101 a to 101 o. The level-up reels 102 a to 102 e each having a larger diameter than those of the reels 101 a to 101 o are disposed at outer peripheral sides of the reels 101 a to 101 o. The level-up reels 102 a to 102 e each disposed so as to enclose three of the reels 101 a to 101 o provided in a column direction are provided with level-up symbols (second symbols) 120 superimposed on symbols (first symbols) arranged on the reels 101 a to 101 o. In the symbol display area 28, eight basic lines BL are set along the column and row directions.

In the embodiments of the present invention, in the symbol display area 28, any of symbols “Blank”, “1Bar”, “2Bar, “3Bar”, “7”, and “WILD” is rearranged on the reels 101 a to 101 o. Symbols “Blank” or “WILD” are rearranged on the level-up reels 102 a to 102 e disposed at outer peripheral sides of the reels 101 a to 101 o in the column direction. A payout is awarded based on level-up symbols 120 rearranged in a superimposed manner on the above rearranged symbols. In this case, the symbols “7” are rearranged on the reels 101 a, 101 d, 101 g, 101 j. The symbols “1Bar” are rearranged on the reel 101 b, 101 f, 101 h, 101 l, 101 o. The symbols “Blank” are rearranged on the other reels. Next, when the level-up symbols 120 of “WILD” are rearranged in a superimposed manner on the reels 101 a, 101 b, 101 c, 101 h, 101 i, 101 m, 101 n, by means of the level-up reels 102 a to 102 e, a payout corresponding to the symbols rearranged on the reels 101 a, 101 b, 101 c, 101 h, 101 i, 101 l, 101 m, 101 n, are determined based on the symbols “WILD”.

FIG. 2 is a view schematically depicting a frame format of an appearance of the slot machine according to the first embodiment. The gaming media used in the slot machine 10 include coins, bills, or electronic value information equivalent thereto. In the present invention, however, the gaming media are not limitative thereto in particular, and can include medals, tokens, electric money, and tickets, for example. The above tickets are not limitative in particular, and can include barcode-attached tickets or the like, as described later, for example.

The slot machine 10 is provided with a cabinet 11, a top box 12 installed on an upper side of the cabinet 11, and a main door 13 provided on a front surface of the cabinet 11.

A lower image display panel 16 serving as a display device is provided in front of the main door 13. The lower image display panel 16 is provided with a liquid crystal panel to display various types of information or images such as effect images during the play of the game.

A symbol display area 28 for displaying symbols is provided at the center of the lower image display panel 16. In the symbol display area 28, nine display windows 103 a to 103 o are formed which allow a rear side thereof to be visually recognized. As shown in FIG. 3, fifteen reels 101 a to 101 o are rotatably provided. In addition, the reels 101 a to 101 o form a double-layered structure with the level-up reels 102 a to 102 e that rotate outside the reels 101 a to 101 o. The level-up reels 102 a to 102 e are each disposed so as to enclose three of the reels 101 a to 101 o provided in the column direction. The outside level-up reels 102 a to 102 e and the inside rotational reels 101 a to 101 o have independent rotational axes, respectively. The rotational axes of the level-up reels 102 a to 102 e are positioned closer to a rear side compared to those of the reels 101 a to 101 o when viewed from the symbol display area 28. These axes are rotationally driven by means of separate motors. A symbol line made up of the symbols “Blank”, “1Bar”, “2Bar”, “3Bar”, “7”, and “WILD” is drawn on the outer peripheral surface of each of the reels 101 a to 101 o. On the other hand, a half periphery of each of the level-up reels 102 a to 102 o is transparent so that the reels 101 a to 101 o can be visually recognized. The remaining half perimeter has the level-up symbols made up of “Blank” and “WILD” drawn thereon in a manner that the symbols drawn on the reels 101 a to 101 o can be visually recognized.

In the lower image display panel 16, six basic lines BL are set along the column or row directions of the symbol display area 28. The basic lines BL serving as the winning lines specify combinations of symbols.

A credit amount display unit 31 of the lower image display panel 16 displays the number of coins credited by way of an image. A payout amount display unit 32 displays by way of an image the number of coins to be paid if a predetermined combination of symbols are rearranged on the winning line.

Provided on a lower side of the lower image display panel 16 are a control panel 20 having a plurality of buttons 23 to 27 through which command regarding the process of the game will be input by a player, a coin receiving slot 21 for receiving coins into the cabinet 11, and a bill validator 22.

On the control panel 20, a start button 23, a change button 24, a cashout button 25, a 1-BET button 26, and a max-BET button 27 are provided. The start button 23 is intended for entering a command for starting the game. The change button 24 is intended for use in asking an attendant of the gaming facility for change. The cashout button 25 is intended for entering a command for paying the credited coins to a coin tray 18 through a coin payout exit 19.

The 1-BET button 26 is intended for entering a command for betting one coin among the credited coins on the game. The max-BET button 27 is intended for entering a command for betting the upper number (50 in this embodiment) of coins that can be bet per game among the credited coins on the game.

The bill validator 22 validates whether or not a bill is legitimate and accepts a legitimate bill into the cabinet 11. The bill validator 22 may be configured so that a barcode-attached ticket 39 described later is readable thereby. Provided on a lower front surface of the main door 13, that is, at a lower part of the control panel 20, is a berry glass 34 on which characters of the slot machine 10 and the like are depicted.

On a front surface of the top box 12, an upper image display panel 33 is provided. The upper image display panel 33 has a liquid crystal panel, which displays images for introducing the game contents or explaining game rules, for example.

Also, on the top box 12, a lamp 30 and a speaker 29 are provided. On a lower side of the upper image display panel 33, a ticket printer 35, a card reader 36, a data display 37, and a key pad 38 are provided. The ticket printer 35 prints on the ticket, a barcode having encoded thereon data such as the credit amount, the date and time, and the identification number of the slot machine 10, and outputs the printed ticket as the barcode-attached ticket 39. The player can play the game on another slot machine with the barcode attached ticket 39 by causing this slot machine to read the barcode attached ticket 39. Alternatively, the player can exchange the barcode-attached ticket 39 with the bills or the like at a predetermined place (at a cashier inside a casino, for example) of the gaming facility.

The card reader 36 reads data from and write data into a smart card. The smart card is to be owned by the player, which stores data for identifying the player or data regarding the log of games executed by the player, for example. The smart card may store data corresponding to coins, bills, or a credit. As an alternative of a smart card, a magnetic stripe card may be employed. The data display 37 is made up of a fluorescent display and the like, and displays the data read by the card reader or the data input by the player through the key pad 38, for example. The key pad 38 inputs data and commands regarding the ticket issuance or the like.

FIG. 4 is a block diagram depicting the internal construction of the slot machine shown in FIG. 2. A gaming board 50 includes: a CPU (Central Processing Unit) 51, a ROM (Read Only Memory) 55 and a boot ROM 52 interconnected by an internal bus; a card slot 53S corresponding to a memory card 53; and an IC socket 54S corresponding to a GAL (Generic Array Logic) 54.

A memory card 53 is composed of a non-volatile memory, such as CompactFlash (registered trademark), and stores a game program. The game program includes a symbol selection program. The symbol selection program is intended for determining symbols to be rearranged in the display windows 103 a to 103 o inside the symbol display area 28. The symbol selection program includes symbol weighing data corresponding to each of a plurality of kinds of payout ratios (for example, 80%, 84%, and 88%). The symbol weighing data is indicative of the correspondence relationship between a code number of each of symbols and level-up symbols, and one or more random number values which come under a predetermined numerical range (0 to 256), with respect to each of the reels 101 a to 101 o and the level-up reels 102 a to 102 e. The payout ratio is determined according to the payout-ratio setting data output from the GAL 54. The symbols to be stopped and displayed are determined depending upon the symbol weighing data corresponding to this payout ratio.

Also, the card slot 53S is configured to allow the memory card 53 to be inserted thereinto or ejected therefrom, and is connected to a motherboard 40. Accordingly, the memory card 53 can be ejected from the card slot 53S, other game programs and other game system programs can then be written into the memory card 53, and further, the memory card 53 can be inserted into the card slot 53S, thereby allowing the player to change the types and contents of games executed in the slot machine 10. The game program includes a program related to a game progress. Furthermore, the game program includes image data or sound data to be output during the game. The image data include, for example, image data indicative of the symbol matrix.

The GAL 54 is a type of a PLD having a fixed OR array structure. The GAL 54 includes plural input ports and plural output ports. Where predetermined data is input to the input port, the GAL 54 outputs data corresponding to the aforementioned data from the output port. The data output from this output port is equivalent to the aforementioned payout-ratio setting data. Further, the IC socket 54S is configured to allow the GAL 54 to be attached thereto and detached therefrom, and is connected to the motherboard 40 by a PCI bus. Accordingly, the GAL can be replaced with the replacement GAL 54 to change the payout-ratio setting data.

The CPU 51, the ROM 55, and the boot ROM 52 interconnected by the internal bus are connected to the motherboard 40 by the PCI bus. The PCI bus serves to transmit signals between the motherboard 40 and the gaming board 50 and supply power from the motherboard 40 to the gaming board 50.

The motherboard 40 is constructed using a general-purpose motherboard commercially available (a printed circuit board on which essential parts of a personal computer are mounted) and includes: a main CPU 41, a ROM (Read Only Memory) 42; a RAM (Random Access Memory) 43; and a communication interface 44.

The ROM 42 is made up of a memory device such as a flash memory and stores thereon a program such as BIOS (Basic Input/Output System) executed by the main CPU 41, and permanent data. When the BIOS is executed by the main CPU 41, processing of initializing predetermined peripheral devices is carried out and processing of capturing game programs and game system programs stored in the memory card 53 through the gaming board 50 is started. In the present invention, the contents of the ROM 42 may be rewritable or not.

The RAM 43 stores data and a program used when the main CPU 41 is activated. The RAM 43 can also store game programs. The RAM 43 further stores data concerning the credit amount, the number of coin-in or coin-out for one game, and the like.

Both a main body PCB (Printed Circuit Board) 60 and a door PCB 80, which will be described later, are connected to the motherboard 40 by USB. A power supply unit 45 is also connected to the motherboard 40.

Connected to the main body PCB 60 and the door PCB 80 are: equipment and devices which generate input signals to be input to the main CPU 41; and equipment and devices of which operations are controlled by a control signal output from the main CPU 41. The main CPU 41 executes a game program stored in the RAM 43 based on an input signal having been input to the main CPU 41 and performs a predetermined computational process, thereby storing results thereof in the RAM 43 or transmitting a control signal to each of equipment and devices as a control process therefor.

Connected to the main body PCB 60 are a lamp 30, a reel controller 72, a hopper 66, a coin detecting section 67, a graphic board 68, a speaker 29, a touch panel 69, a bill validator 22, a ticket printer 35, a card reader 36, a key switch 38S, and a data display 37. The lamp 30 illuminates in a predetermined pattern, based on a control signal output from a main CPU 41.

As shown in FIG. 5, a sub CPU 61 included in the reel controller 72 controls rotation and stop of the reels 101 a to 101 o and the level-up reels 102 a to 102 e. A motor driving circuit 62 including an FPGA (Field Programmable Gate Array) 63 and a driver 64 are connected to the sub CPU 61. The FPGA 63 is an electronic circuit, such as a programmable LSI, and functions as a control circuit of stepping motors 70 and 71. The driver 64 functions as an amplifier circuit of a pulse input to the stepping motors 70 and 71. The motor driving circuit 62 is connected to stepping motors 70 a to 70 o that rotate the reels 101 a to 101 p, respectively, and stepping motors 90 a to 90 e that rotate the level-up reels 102 a to 102 e, respectively. The stepping motors 70 and 90 are stepping motors of one-two phase excitation mode.

In addition, an index detection circuit 65 and a position change detection circuit 71 are connected to the sub CPU 61. The index detection circuit 65 detects positions (indices described later) of the reels 101 a to 101 o and the level-up reels 102 a to 102 e being rotated. Further, the index detection circuit 65 can detect loss of synchronization between the reels 101 a to 101 o and the level-up reels 102 a to 102 e.

The position change detection circuit 71 detects change of positions where the reels 101 a to 101 o and the level-up reels 102 a to 102 e stop after rotation. For example, the position change detection circuit 71 detects change of positions where the reels 101 a to 101 o and the level-up reels 102 a to 102 e are stopped, in the case where a player forcibly changes the positions which actually do not result in a winning combination, to the positions corresponding to a winning combination. The position change detection circuit 71 is constituted so as to detect change of the positions of the reels 101 a to 101 o and the level-up reels 102 a to 102 e by detecting, for example, fins (not shown) mounted at predetermined intervals to an inner part of the reels 101 a to 101 o and the level-up reels 102 a to 102 e.

The hopper 66 is installed in the cabinet 11 and pays out a predetermined number of coins from the coin payout exit 19 to the coin tray 18 based on a control signal output from the main CPU 41. The coin detecting section 67 is installed inside the coin payout exit 19 and outputs an input signal to the main CPU 41 upon detecting that a predetermined number of coins have been paid out from the coin payout exit 19.

The graphic board 68 controls, based on a control signal output from the main CPU 41, images to be displayed on the upper image display panel 33 and the lower image display panel 16. The credit amount stored in the RAM 43 is displayed on a credit amount display section (not shown) of the lower image display panel 16. The number of coins to be paid out is displayed at a payout amount display section (not shown) of the lower image display panel 16. The graphic board 68 is equipped with a VDP (Video Display Processor) which generates image data based on a control signal output from the main CPU 41 and a video RAM which temporarily stores image data generated by the VDP, and the like. The image data used in generating image data with VDP is contained in the game program read from the memory card 53 and stored in the RAM 43.

The bill validator 22 validates whether or not a bill is legitimate and accepts a legitimate bill into the cabinet 11. Upon accepting a legitimate bill, the bill validator 22 outputs an input signal to the main CPU 41 based on the amount of the bill. The main CPU 41 stores in the RAM 43 the credit amount corresponding to the amount of bills transmitted by the input signal.

Based on a control signal output from the main CPU 41, the ticket printer 35 prints on a ticket a barcode having encoded thereon data such as the credit amount, data and time, and the identification number of the slot machine 10 stored in the RAM 43. Further, this printer outputs the printed ticket as a barcode-attached ticket 39. The card reader 36 transmits to the main CPU 41 the data read from the smart card and writes the read data onto the smart card, based on a control signal from the main CPU 41. The key pad switch 38S is provided on the key pad 38, and outputs a predetermined input signal to the main CPU 41 when the player operates the key pad 38. The data display 37, based on a control signal output from the main CPU 41, displays the data read by the card reader 36 and the data input by the player through the key pad 38.

A control panel 20, a reverter 21S, a coin counter 21C, and a cold cathode tube 81 are connected to a door PCB 80. The control panel 20 is provided with: a start switch 23S corresponding to the start button 23; a change switch 24S corresponding to the change button 24; a cashout switch 25S corresponding to a cashout button 25; a 1-BET switch 26S corresponding to a 1-BET button 26; and a max-BET switch 27S corresponding to the max BET button 27. When the player operates the buttons 23 to 27, the corresponding switches 23S to 27S output input-signals to the main CPU 41, respectively.

The coin counter 21C is provided inside the coin receiving slot 21, and validates whether or not a legitimate coin is inserted into the coin receiving slot 21. Those other than the legitimate coins are discharged from the coin payout exit 19. The coin counter 21C outputs an input signal to the main CPU 41 when a legitimate coin is detected.

The reverter 21S operates based on a control signal output from the main CPU 41 and distributes coins recognized as being legitimate by the coin counter 21C into a cash box (not shown in the drawings) or the hopper 66 which is arranged in the slot machine 10. In other words, when the hopper 66 is filled with coins, legitimate coins are distributed by the reverter 21S into the cash box. On the other hand, when the hopper 66 is not filled with coins, legitimate coins are distributed into the hopper 66. A cold cathode tube 81 functions as a backlight installed on rear face side of each of the lower image display panel 16 and the upper image display panel 33, and is lit up based on a control signal output from the main CPU 41.

FIG. 6 is a view showing a correspondence relationship between each of various symbols and payouts. A table indicative of this correspondence relationship between various types of symbols and payouts is stored in the ROM 42 and is used to determine the payout. As shown in FIG. 6A, where a predetermined symbol is rearranged on a winning line on which the player has bet, LIN payout is determined based on a winning combination. Furthermore, where the predetermined number of identical symbols are rearranged in the symbol display area 28, as shown in FIG. 6B, ANY payment is determined based on a winning combination. The LIN payout is obtained in the case where a winning combination appears as one of the combinations of symbols “7-7-7”, “3Bar-3Bar-3Bar”, “2Bar-2Bar-2Bar”, and “1Bar-1Bar-1Bar” on the basic line BL as the winning lines set in symbol display area. The ANY payout is obtained according to the number of symbols, “WILD”, “7”, “3Bar”, “2Bar”, and “1Bar”, which are rearranged in the symbol display area 28.

FIGS. 7A and 7B are views each showing one example of an image displayed in the slot machine shown in FIG. 2 according to the first embodiment. FIG. 7A is a view showing one example of symbol rearrangement according to the first embodiment. FIG. 7B is a view showing one example of level-up symbol rearrangement according to the first embodiment. As shown in FIG. 7A, the lower image display panel 16 is made up of display-related sections such as a display area section 92, an information display section 93, and an effect image display section 94. The display area section 92 is for displaying a symbol matrix SM. In addition, the information display section 93 is arranged above the display area section 92. This display section is made up of a credit amount display section 93 a, a BET amount display section 93 b, a character information display portion 93 c, a PAID amount display section 93 d, and a charge display section 93 e.

The number of coins presently credited is displayed at the credit amount display section 93 a while the number of coins bet in one game is displayed at the BET amount display section 93 b. The character information indicative of a current status of the game is displayed at the character information display section 93. The characters of “PLAYNOW” are displayed during the play of the game, whereas the characters of “GAMEOVER” are displayed at the intervals between the plays of the game. The number of coins that has been successfully obtained in one game is displayed at the PAID amount display section 93 d, whereas a conversion value of the credit amount based on a predetermined charge is displayed at the charge display section.

At the effect image display section 94, effect images in accordance with a type of the present slot game are displayed. Therefore, the effect image display section 94 displays effects images which are different depending on the basic and free games.

In the symbol display area 28 of the lower image display panel 16, when the reels 101 a to 101 o are stopped, a total of fifteen symbols in three rows and five columns are rearranged in the display window 103. In the display window 103, any of the symbols “Blank”, “1Bar”, “2Bar”, “3Bar”, “7”, and “WILD” is rearranged. In this case, when the reels 101 a to 101 o are stopped, the symbols “7” are rearranged in the reels 101 a, 101 d, 101 g, 101 j; the symbols “1Bar” are rearranged in the reels 101 b, 101 f, 101 h, 101 l, 101 o; and the symbols “Blank” are rearranged in the other reels.

As shown in FIG. 7B, after any of the symbols “Blank”, “1Bar”, “2Bar”, “3Bar”, “7”, and “WILD” is rearranged in the display windows 103 inside the symbol display area 28 of the lower image display panel 16, the level-up reel 102 a to 102 e are stopped, and then, the level-up symbols 120 are rearranged. In this case, when the level-up symbol 120 of “WILD” are rearranged in a superimposed manner on the reels 101 a, 101 b, 101 c, 101 h, 101 i, 101 m, 101 n, a payment is determined for the symbols rearranged on the reels 101 a, 101 b, 101 c, 101 h, 101 i, 101 m, and 101 n, based on the symbols “WILD”, so that a prize is awarded.

Next, a process executed in the slot machine 10 according to the first embodiment will be described in detail with reference to the accompanying drawings. The main CPU 41 reads out and executes a game program, thereby conducting the game.

FIG. 8 is a flowchart showing a subroutine of a main process. In the main process, when a power switch is turned on (that is, when power is supplied) first, a motherboard 40 and a gaming board 50 are activated respectively, and then, the CPU 51 executes an initial setting process (step S101). In the initial setting process, the main CPU 41 executes a BIOS stored in the ROM 42 to decompress the compressed data incorporated in the BIOS to the RAM 43, and executes the BIOS decompressed in the RAM 43, and performs diagnosis and initialization of each of the peripheral devices. Further, the main CPU 41 writes game programs or the like from the ROM 42 into the RAM 43, and acquires payout-ratio setting data and country-identification information. The main CPU 41 also performs an authentication process for each program during execution of the initial setting process.

Next, the main CPU 41 performs a game execution process described later with reference to FIG. 9 (step S102). In the game execution process, the main CPU 41 sequentially reads and executes game programs or the like from the ROM 42. By performing the game execution process, the slot machine 10 executes the game according to the first embodiment. The game execution process is repeatedly performed while power is supplied to the slot machine 10.

FIG. 9 is a flowchart showing a subroutine of the game execution process invoked and performed at step S102 of the subroutine shown in FIG. 8. First, the main CPU 41 judges whether or not a coin has been bet (step S201). Specifically, the main CPU 41 judges whether an input signal output from the 1-BET switch 26S at the time of operation of the 1-BET button 26 has been received or whether an input signal output from the max BET switch 27S at the time of operation of the max BET switch 27S has been received. The main CPU 41 controls the current step to return to the process at the step S201 upon judging that no coin has been bet (step S201: NO).

On the other hand, the main CPU 41 subtracts the number of bet coins from the credit amount stored in the RAM 43 upon judging that a coin has been bet (step S201: YES). Where the number of bet coins is larger than the credit amount stored in the RAM 43, the main CPU 41 controls the current step to return to step S201 without performing the process for subtracting (step S202) the number of bet coins from the credit number stored in the RAM 43. Where the number of bet coins exceeds the upper limit (50 coins in this embodiment) of coins that can be bet in one game, the main CPU 41 controls the step to return to step 203 without performing the process for subtracting the number of bet coins from the credit number stored in the RAM 43.

At step S203, the main CPU 41 judges whether or not the start button 23 has been set to ON (step S203). Specifically, the main CPU 41 judges whether or not an input signal output from the start switch 23S at the time of pushing of the start button 23 has been received. The main CPU 41 controls the step to return to step 201 upon judging that the start button 23 has not been set to ON (step S203: NO). Where the start button 23 has not been set to ON (for example, where an instruction has been input to terminate the game without setting the start button 23 to ON), the main CPU 41 cancels acceptance of a subtraction result at step S202.

On the other hand, when the main CPU 41 judges that the start button 23 has been set to ON (step S203: YES), the main CPU 41 carries out symbol rearrangement process which will be described later with reference to FIG. 10 (step S204). Specifically, with respect to the symbols and the level-up symbols rearranged on the lower image display panel 16, the CPU 41 executes a program stored in the RAM 43 to sample a random number value from a numerical value range of a predetermined random number value range. On the basis of the sampled random number value and symbol weighing data, the CPU 41 determines and rearranges the symbols “Blank”, “1Bar”, “2Bar”, “3Bar”, “7”, and “WILD”, and the level-up symbols “Blank” and “WILD”.

Next, the main CPU 41 judges whether a prize is established or not (step S205). Specifically, the main CPU 41 judges whether or not a combination of symbols rearranged in the symbol display area 28 is a winning combination in which any payout is performed. In this case, the prize is established when a winning combination appears, the winning combination based on a combination of the symbols rearranged on the basic line BL as the winning line or based on the number of symbols rearranged in the symbol display area 28 (see FIG. 6).

Upon judging that the prize is established (step S205: YES), the main CPU 41 then performs a coin-payout process in accordance with the bet amount and the number of coins set for the winning combination (step S206). Where the coins are deposited, the main CPU 41 performs a process for adding the number of paid-out coins to the credit amount stored in the RAM 43. On the other hand, upon execution of the coin-payout process, the main CPU 41 pays out the predetermined number of coins by transmitting a control signal to the hopper 66.

On the other hand, upon judging that the prize is not established (step S205: NO), or when the main CPU 41 executes the process of step S206, the main CPU 41 judges whether or not a bonus game trigger is established (step S207). Specifically, the main CPU 41 executes a program stored in the RAM 43 to sample a random number value from a numerical value range of a predetermined random number value range. On the basis of the sampled random number value, the main CPU 41 judges whether or not the bonus game trigger is established. When the main CPU 41 judges that the bonus game trigger is established (step S207: YES), the main CPU 41 carries out a bonus game execution process (step S208). In the bonus game execution process, the main CPU 41 sequentially reads and executes game programs or the like from the ROM 42 to carry out the bonus game execution process.

On the other hand, when the main CPU 41 judges that the bonus game trigger is not established (step S207: NO) or when the main CPU 41 executes the process in step S208, the main CPU 41 terminates the game execution process.

FIG. 10 is a flowchart showing a subroutine of the symbol rearrangement process invoked and executed in step S204 of the subroutine shown in FIG. 9. First, the main CPU 41 displays symbols in the symbol display area 28 in a scrolling manner (step S301). Specifically, the main CPU 41 starts rotation of the reels 101 a to 101 o. At this time, in the symbol display area 28, six basic lines BL are set along the column or row direction.

Next, the main CPU 41 carries out a symbol determining process (step S302). Specifically, with respect to symbols rearranged in the symbol display area 28, the CPU 41 executes a program stored in the RAM 43 to sample a random number value from a numerical value range of a predetermined random number value range. On the basis of the sampled random number value and symbol weighing data, from among the symbols “Blank”, “1bar”, “2Bar”, “7”, and “WILD”, and the level-up symbols “Blank” and “WILD”, the CPU 41 determines those to be rearranged in the symbol display area 28.

Next, the main CPU 41 carries out rearrangement of symbols (step S303). Specifically, the main CPU 41 stops rotation of the reels 101 a to 101 o so as to display, in a stopped manner, the symbols determined at step S302, thereby rearranging the symbols (see FIG. 7A).

Next, the main CPU 41 stores the rearranged symbols (step S304). Specifically, the main CPU 41 stores in the RAM 43 the symbols rearranged in the symbol display area 28 at step S303.

First, the main CPU 41 displays level-up symbols in the symbol display area 28 in a scrolling manner (step S305). Specifically, the main CPU 41 starts rotation of the level-up reels 102 a to 102 e.

Next, the main CPU 41 carries out rearrangement of level-up symbols (step S306). Specifically, the main CPU 41 stops rotation of the level-up reels 103 a to 103 e so as to display, in a stopped manner, the level-up symbols determined at step S302, thereby rearranging the level-up symbols (see FIG. 7B).

Next, the main CPU 41 judges whether or not a payout of symbols is higher than that of previously arranged ones (step S307). Specifically, the main CPU 41 judges whether or not a payout of the symbols stored in step S304 is higher than that of level-up symbols after rearranged. When the main CPU 41 judges that the payout of the symbols is higher than that of the previously arranged ones (step S307: YES), the main CPU 41 determines a payout based on the level-up symbols (step S308). For example, in the case where the level-up symbol 120 of “WILD” is rearranged on the symbol “1Bar” in a superimposed manner, a level of the symbol “1Bar” is increased to that of the symbol “WILD”, so that a payout that is to be awarded in the case where the symbol “WILD” is rearranged is determined (see FIG. 7B). The main CPU 41 terminates the symbol rearrangement process when executing the process in step S308.

On the other hand, when the main CPU 41 judges that a payout of the symbols is not higher than that of the previous one (step S307: NO), the main CPU 41 determines a payout based on the symbols (step S309). For example, in case a combination of the symbols stored in step S304 is a winning combination and the combination of the symbols is no longer a winning combination due to the level-up symbols rearranged at step S306, a payout is determined based on the winning combination of the symbols stored in step S304. The main CPU 41 terminates the symbol rearrangement process when executing the process in step S309.

Next, a slot machine 10 according to a second embodiment will be described with reference to the accompanying drawings. The slot machine according to the third embodiment below has an appearance, a circuit configuration, and the like that are substantially the same as those of the slot machine 10 according to the first embodiment of the present invention. Thus, a duplicated explanation is omitted hereinafter. In addition, the constituent elements corresponding to those of the slot machine 10 are designated by the same reference numerals and are explained.

FIG. 11 is a flowchart showing a subroutine of the game execution process according to the second embodiment, the process being invoked and performed at step S102 of the subroutine shown in FIG. 8. First, the main CPU 41 judges whether or not a coin has been bet (step S401). Specifically, the main CPU 41 judges whether an input signal output from the 1-BET switch 26S at the time of operation of the 1-BET button 26 has been received or whether an input signal output from the max BET switch 27S at the time of operation of the max BET switch 27 has been received. The main CPU 41 controls the current step to return to the process at the step S401 upon judging that no coin has been bet (step S401: NO).

On the other hand, the main CPU 41 subtracts the number of bet coins from the credit amount stored in the RAM 43 (step S402) upon judging that a coin has been bet (step S401: YES). Where the number of bet coins is larger than the credit amount stored in the RAM 43, the main CPU 41 controls the current step to return to step S401 without performing the process for subtracting the number of bet coins from the credit number stored in the RAM 43. Where the number of bet coins exceeds the upper limit (50 coins in this embodiment) of coins that can be bet in one game, the main CPU 41 controls the step to return to step 403 without performing the process for subtracting the number of bet coins from the credit number stored in the RAM 43.

At step S403, the main CPU 41 judges whether or not the start button 23 has been set to ON (step S403). Specifically, the main CPU 41 judges whether or not an input signal output from the start switch 23S at the time of pushing of the start button 23 has been received. The main CPU 41 controls the step to return to step 401 upon judging that the start button 23 has not been set to ON (step S403: NO). Where the start button 23 has not been set to ON (for example, where an instruction has been input to terminate the game without setting the start button 23 to ON), the main CPU 41 cancels acceptance of a subtraction result at step S402.

On the other hand, the main CPU 41 performs a symbol rearrangement process of the basic game (step S404) upon judging that the start button 23 has been set to ON (step S403: YES). Specifically, with respect to symbols and level-up symbols rearranged on the lower image display panel 16, the CPU 41 executes a program stored in the RAM 43 to sample a random number value from a numerical value range of a predetermined random number value range. On the basis of the sampled random number value and symbol weighing data, the CPU 41 determines and rearranges the symbols “Blank”, “1Bar”, “2Bar”, “3Bar”, “7”, and “WILD”, and the level-up symbols “Blank” and “WILD”.

Next, the main CPU 41 judges whether or not a prize has been established (step S405). Specifically, the main CPU 41 judges whether or not a combination of symbols rearranged in the symbol display area 28 is a winning combination in which any payout is performed. In this case, the prize is established when a winning combination appears, the winning combination based on a combination of the symbols rearranged on the basic line BL as the winning line or based on the number of symbols rearranged in the symbol display area 28 (see FIG. 6).

Thereafter, upon judging that the prize has been established (step S405: YES), the main CPU 41 performs a coin-payout process in accordance with the bet amount and the number of coins set for the winning combination (step S406). Where the coins are deposited, the main CPU 41 performs a process for adding the number of paid-out coins to the credit amount stored in the RAM 43. On the other hand, upon execution of the coin-payout process, the main CPU 41 pays out the predetermined number of coins by transmitting a control signal to the hopper 66.

On the other hand, the main CPU 41 judges whether a free game trigger has been established or not (step S407) when judging that the prize has not been established (step S405: NO) or when executing the process at step S406. Specifically, the main CPU 41 executes the program stored in the RAM 43 to sample the random numeric values in a numerical range which comes under a predetermined range of random numeric values, thereby judging whether or not the free game trigger condition has been satisfied based on the sampled random numeric values. Upon judging that the free game trigger is established (step S407: YES), the main CPU 41 performs a free-game execution process described later with reference to FIG. 12 (step S408). In this free-game execution process, the main CPU 41 sequentially reads and executes the game programs or the like from the ROM 42 and performs the free-game execution process.

On the other hand, the CPU 41 terminates the game execution process when judging that the free game trigger is not established (step S407: NO) or when executing the process at step S408.

FIG. 12 is a flowchart showing a subroutine of a free-game execution process according to the second embodiment, the process being invoked and executed at step S408 of the subroutine shown in FIG. 11. First, the main CPU 41 determines a free-game number T as a number of times in executing the free game (step S501). Specifically, the main CPU 41 executes the program stored in the RAM 43, thereby reading the number of times in executing the free game that is set in association with a random number using a random numeric value sampled in a numerical range which comes under a predetermined range of random numeric values 1 to 256. After that, the main CPU 41 determines the free-game number T.

Next, the main CPU 41 sets the free-game number B to T (step S502). Specifically, the main CPU 41 sets B=T to a value of the remaining free-game number stored in a storage area of data indicative of the number of remaining games, the area being set in the RAM 43. A value of T is equal to the free-game number T determined at step S501.

The main CPU 41 then judges whether the start button 23 has been set to ON or not (step S503). Specifically, the main CPU 41 judges whether or not an input signal output from the start switch 23S at the time of pushing of the start button 23 has been received. The main CPU 41 controls the step to return to step S503 upon judging that the start button 23 has not been set to ON (step S503: NO).

Upon judging that the start button 23 has been set to ON (step S503: YES), the main CPU 41 performs a process for displaying effect images (step S504). Specifically, the main CPU 41 displays a free-game-number display images 90 a (see FIG. 14) corresponding to the free-game number on the upper image display panel 33.

Next, the main CPU 41 performs a symbol rearrangement process of the free game described later with reference to FIG. 13 (step S505). Specifically, the CPU 41 executes a program stored in the RAM 43 and determines the symbols to be rearranged in symbol matrix elements SM, from among the symbols “Blank”, “1Bar”, “2Bar”, “3Bar”, “7”, and “WILD”. This determination is based on the symbol weighting data and random numeric values sampled by sampling the random numeric values in a numerical range which comes under a predetermined range of random numeric values. The CPU 41 then rearranges the symbols in the display windows 103 a to 103 o inside the symbol display area 28 displayed on the lower image display panel 16.

Next, the main CPU 41 judges whether or not a prize has been established (step S506). Specifically, the main CPU 41 judges whether or not a combination of symbols rearranged in the display windows 103 inside the symbol display area 28 is a winning combination in which any payout is performed. In this case, the prize is established when a winning combination appears, the winning combination based on a combination of the symbols rearranged on the basic line BL as the winning line or based on the number of symbols rearranged in the symbol display area 28 (see FIG. 6).

Thereafter, upon judging that the prize has been established (step S506: YES), the main CPU 41 performs a coin-payout process in accordance with the bet amount and the number of coins set for the winning combination (step S507). Where the coins are deposited, the main CPU 41 performs a process for adding the number of paid-out coins to the credit amount stored in the RAM 43. On the other hand, upon execution of the coin-payout process, the main CPU 41 pays out the predetermined number of coins by transmitting a control signal to the hopper 66.

On the other hand, upon judging that the prize has not been established (step S506: NO), or executing the process at step S507, the main CPU 41 sets the remaining free-game number B to B−1 (step S508). Specifically, the main CPU 41 sets B=B−1 at a value of the free-game number B stored in the RAM 43.

The main CPU 41 then judges whether the number of symbols “WILD” is equal to fifteen or not (step S509). Specifically, the main CPU 41 judges whether or not the symbols “WILD” have been rearranged in all of the display windows 103 a to 103 o inside the symbol display area 28 (see FIG. 14C). Upon judging that the symbols “WILD” have been rearranged in all of the display windows 103 a to 103 o (step S509: YES), the main CPU 41 performs the coin-payout process in accordance with the bet amount and the number of coins set for the winning combination (step S510). Where the coins are deposited, the main CPU 41 performs a process for adding the number of paid-out coins to the credit amount stored in the RAM 43. On the other hand, upon execution of the coin-payout process, the main CPU 41 pays out the predetermined number of coins by transmitting a control signal to the hopper 66. The main CPU 41 controls the current step to shift to the process at step S512.

On the other hand, upon judging that the number of symbols “WILD” is not equal to fifteen (step S509: NO), the main CPU 41 judges whether or not the remaining free-game number B is equal to zero (step S511). Specifically, the main CPU 41 judges whether or not a value of the remaining game number stored in the RAM 43 is equal to zero. Upon judging that the value of the remaining free-game number B is not zero (step S511: NO), the main CPU 41 controls the step to return to step S503. On the other hand, upon executing the process at step S510 or judging that a value of B is equal to zero (step S511: YES), the main CPU 41 performs a free-game termination process (step S512). Specifically, the main CPU 41 terminates a control operation over the level-up reels at step S607 in FIG. 13 to be described later. The main CPU 41 terminates the free-game execution process when executing the process at step S512.

FIG. 13 is a flowchart showing a subroutine of the symbol rearrangement process of the free game according to the second embodiment, the process being invoked and executed at step S505 of the subroutine shown in FIG. 12. First, the main CPU 41 displays symbols in the symbol display area 28 in a scrolling manner (step S601). Specifically, the main CPU 41 starts rotation of the reels 101 a to 101 o. At this time, in the symbol display area 28, six basic lines BL are set along the column or row direction.

Next, the main CPU 41 carries out a symbol determination process (step S602). Specifically, with respect to symbols rearranged in the symbol display area 28, the CPU 41 executes a program stored in the RAM 43 to sample a random number value from a numerical value range of a predetermined random number value range. On the basis of the sampled random number value and symbol weighing data, from among the symbols “Blank”, “1Bar”, “2Bar”, “3Bar”, “7”, and “WILD”, and the level-up symbols “Blank” and “WILD”, the CPU 41 determines those to be rearranged in the symbol display area 28.

Next, the main CPU 41 carries out rearrangement of symbols (step S603). Specifically, the main CPU 41 stops rotation of the reels 101 a to 101 o so as to display, in a stopped state, the symbols determined at step S602, thereby rearranging the symbols.

Next, the main CPU 41 displays level-up symbols in the symbol display area 28 in a scrolling manner (step S604). Specifically, the main CPU 41 starts rotation of the level-up reels 102 a to 102 e.

Next, the main CPU 41 carries out rearrangement of level-up symbols (step S605). Specifically, the main CPU 41 stops rotation of the level-up reels 103 a to 103 e so as to display, in a stopped state, the level-up symbols determined at step S602, thereby rearranging level-up symbols (see FIG. 14B).

The main CPU 41 then judges whether or not the number of symbols “WILD” on the basic line in a column direction is equal to three (step S606). Specifically, the main CPU 41 judges whether or not three of the level-up symbols “WILD” are rearranged in the level-up reel 103 a to 103 e in a column direction. Upon judging that the number of symbols “WILD” rearranged in a column direction is not equal to three (step S606: NO), the main CPU 41 terminates the free-game symbol rearrangement process when the process at step S606 is executed.

On the other hand, upon judging that the number of symbols “WILD” rearranged in a column direction is equal to three (step S606: YES), the main CPU 41 controls the level-up reels (step S607). Specifically, the main CPU 41 controls the level-up reels 103 a to 103 e in a manner to stop rotation of the level-up reels 103 having three of the level-up symbols 120 of “WILD” rearranged thereon, on the basic line in a column direction during the free game. The main CPU 41 terminates the free-game symbol rearrangement process when executing the process at step S607 (see FIG. 14C).

FIGS. 14A, 14B, and 14C are views each showing one example of an image displayed during the free game in the slot machine shown in FIG. 2 according to the second embodiment. As shown in FIG. 14A, upon start of the free game, the upper image display panel 33 displays the free-game-number display image 90 a indicative of the number of times in executing the free game. In this case, the free-game-number display image 90 a of “10 FREE GAME” is displayed indicating that the number of times in executing the free game has been set to ten.

As shown in FIG. 14B, after any of the symbols “Blank”, “1Bar”, “2Bar”, “3Bar”, “7”, and “WILD” is rearranged in any of the display windows 103 inside the symbol display area 28 of the lower image display panel 16, rotation of the level-up reels 102 a to 102 e is stopped, and then the level-up symbols are rearranged. In this case, when the level-up symbols 120 of “WILD” are rearranged in a superimposed manner on the reels 101 in the display windows 103 a, 103 b, 103 c, 103 g, 103 h, 103 i, 103 m, 103 n, three of the symbols “WILD” are rearranged on each of the level-up reels 102 a and 102 c in a column direction. Therefore, rotation of the level-up reels 102 a and 102 c is stopped during the free game in which the symbols “WILD” are contiguously rearranged.

As shown in FIG. 14C, in the case where fifteen of the symbols “WILD” and the level-up symbol 120 of “WILD” are rearranged in the display windows 103 a to 103 o inside the lower image display panel 16, the main CPU 41 terminates the free game and determines a payout that corresponds to a winning combination of the symbols “WILD” (see FIG. 6).

In the foregoing, while the embodiments of the present invention have been described, these embodiments merely present specific examples. An appropriate design change can be made for the specific configuration of each means or the like. Also, the effects described in the embodiments of the present invention are only listing the most preferable effects arising from the present invention, and the effects of the present invention are not limited to those described in the embodiments of the present invention. 

1. A slot machine, comprising: a symbol matrix display area in which a plurality of symbols are arranged in column and row directions; a plurality of first reels provided corresponding to individual fields of the symbol matrix display area, the first reels having plural types of first symbols arranged thereon respectively; a plurality of second reels each having a larger diameter than that of each of the first reels, the plurality of second reels being disposed at outer peripheral sides of the plurality of first reels so as to enclose part of the plurality of first reels provided in a column direction, the plurality of second reels each having a plurality of second symbols arranged thereon, the second symbols being arranged in a superimposed manner on the first symbols on the first reels disposed in the symbol matrix display area; a plurality of first motors for driving the plurality of first reels, respectively, in a rotational manner; a second motor for driving the second reels in a rotational manner; and a processor for controlling rotation of the first and second reels by controlling the first and second motors, wherein: the plurality of first reels each have an independent rotation axis respectively; the second reels each have a rotation axis positioned closer to a rear side in comparison with that of each of the first reels when viewed from the symbol matrix display area; and the processor is programmed to: (a) control rotation of the plurality of first reels to rearrange, in the symbol matrix display area, the first symbols arranged on the first reels; (b) control rotation of the second reels to rearrange, in the symbol matrix display area, the second symbols arranged on the second reels, so as to superimpose the second symbols arranged on the second reels on the first symbols arranged on the first reels rearranged in the symbol matrix display area; and (c) award a prize in the case where a combination of the first symbols on the first reels rearranged in the symbol matrix display area and the second symbols on the second reels rearranged in a superimposed manner on the first symbols arranged on the first reels is a winning combination on an activated line in a column, row, or diagonal direction.
 2. The slot machine according to claim 1, wherein: each of the second symbols arranged on the second reel is set to a WILD symbol; and the processor, in the itemized (c), awards a prize according to a combination of the first symbols on the first reels disposed in the symbol matrix display area and the plurality of WILD symbols contiguously rearranged on any one of the second reels.
 3. The slot machine according to claim 1, wherein: the second reels each are made up of a predetermined symbol and a blank symbol.
 4. The slot machine according to claim 1, wherein: the processor is further programmed to: (d) execute a basic game; (e) execute a free game in the case where a predetermined condition is met during the basic game; and (f) execute processes in the itemized (a) to (c) during the free game.
 5. A slot machine, comprising: a symbol matrix display area in which a plurality of symbols are arranged in column and row directions; a plurality of first reels provided corresponding to individual fields of the symbol matrix display area, the first reels having plural types of first symbols arranged thereon respectively, a plurality of second reels each having a larger diameter than that of each of the first reels, the plurality of second reels being disposed at outer peripheral sides of the plurality of first reels so as to enclose part of the plurality of first reels provided in a column direction, the plurality of second reels each having a plurality of second symbols arranged thereon, the second symbols being arranged in a superimposed manner on the first symbols on the first reels disposed in the symbol matrix display area; a plurality of first motors for driving the plurality of first reels, respectively, in a rotational manner; a second motor for driving the second reels in a rotational manner; and a processor for controlling rotation of the first and second reels by controlling the first and second motors, wherein: the plurality of first reels each have an independent rotation axis respectively; the second reels each have a rotation axis positioned closer to a rear side compared to those of the first reels when viewed from the symbol matrix display area; each of the second symbols arranged on the second reels is set to a WILD symbol; and the processor is programmed to: (a) control rotation of the plurality of first reels to rearrange, in the symbol matrix display area, the first symbols arranged on the first reels; (b) control rotation of the second reels to rearrange, in the symbol matrix display area, the second symbols arranged on the second reels so as to superimpose the second symbols arranged on the second reels on the first symbols arranged on the first reels rearranged in the symbol matrix display area; and (c) award a prize in the case where a combination of the first symbols on the first reels rearranged in the symbol matrix display area and the WILD symbols on the second reels rearranged in a superimposed manner on the first symbols arranged on the first reels is a winning combination on an activated line in a column, row, or diagonal direction.
 6. The slot machine according to claim 5, wherein: the second reels each are made up of a predetermined symbol and a blank symbol.
 7. The slot machine according to claim 5, wherein: the processor is further programed to: (d) execute a basic game; (e) execute a free game in the case where a predetermined condition is met during the basic game; and (f) execute processes in the itemized (a) to (c) during the free game. 